Prior to using a medical device, the device should be sterile and not exposed to hazardous environments and/or chemicals. Medical devices are used with and inside the human body, and the use of unsterile medical devices can cause infections or even death. In addition, and for at least these reasons, many medical devices are designed as single use devices and should not be reused on a second patient. As it is sometimes difficult to tell by just visual inspection, however, whether a particular medical device is sterile, has been exposed to potentially hazardous environments and/or chemicals, or already used, an indicator of prior use or an unsterile state is desired.
One way to determine that a medical device is sterile is if it is used immediately after removing it from its original, unopened, sealed packaging. However, as there may be a time delay between when the medical device is removed from that packaging and when it is used by the user, and the actual user may differ from the person who removed the medical device from the packaging, this method may be of limited use.
Another way to determine that a medical device is sterile is through the placement of labels, stickers, or tapes on the medical device or packaging. The labels, stickers, or tapes may contain chemicals that change color, for example, when exposed to a nonsterile or other undesirable environment, an undesirable temperature, or a potentially hazardous chemical for any duration. However, labels, stickers, or tapes placed on the device packaging presents the same problems discussed above. In addition, labels, stickers, or tapes can be removed and/or fall off when placed on the medical device itself.
Accordingly, another method of determining the sterility of a medical device is desired.